20050561 has 2 divisors, whose sum is σ = 20050562. Its totient is φ = 20050560.

The previous prime is 20050523. The next prime is 20050573. The reversal of 20050561 is 16505002.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19360000 + 690561 = 4400^2 + 831^2 .

It is a cyclic number.

It is not a de Polignac number, because 20050561 - 2¹¹ = 20048513 is a prime.

It is not a weakly prime, because it can be changed into another prime (20050661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10025280 + 10025281.

It is an arithmetic number, because the mean of its divisors is an integer number (10025281).

Almost surely, 2^20050561 is an apocalyptic number.

It is an amenable number.

20050561 is a deficient number, since it is larger than the sum of its proper divisors (1).

20050561 is an equidigital number, since it uses as much as digits as its factorization.

20050561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 300, while the sum is 19.

The square root of 20050561 is about 4477.7852784608. The cubic root of 20050561 is about 271.6703086234.

Adding to 20050561 its reverse (16505002), we get a palindrome (36555563).

The spelling of 20050561 in words is "twenty million, fifty thousand, five hundred sixty-one".